So I've been looking at different places to get a few prints of some of my landscape photos and possibly selling them, here is my problem though, is there a standard photo ratio for landscapes? Like a regular photo is 2:3 but when I edit my landscapes they are a wide format and I just crop at what looks good for the photo but when I upload to a print site that has wide format prints and canvases I've usually missed the mark for what they have available and most don't give you an option to re-size only crop. So, is there a standard?
Sunset Point by sherpa1d, on Flickr

Mike, are you looking at landscape ratio or panorama print. I would suggest looking at the sizes your print shop has, find the size that meets your needs and crop the photo using the rule top and side to suit the size selected.

I googled your question, below is bits of what I found, guess if you intend to sell them you want to make sure you can get the frame size of your print. It looks like the right ratio size is personal preference.

When I ran a gallery show a few years ago I had the option of getting anything 19" "wide" by whatever I wanted long. Fortunately or unfortunately, I was constrained to a nearly 3:2 ratio, but even as such, the 13"x19" prints were $60 a pop. Definitely expect to pay a premium for the larger and higher-quality prints but trust me when I say that it's more than worth it.

Most of the single sheet models I've seen max out at 13" x 19" (which obviously fits a 2:3 aspect image rather well with a 1/2" border).

Larger than that, you'd probably be looking at 24" x whatever. (Well, not really "whatever" since the paper roll is probably limited to 50 feet or something. But a 1:20 aspect ratio should be doable ... as well as very expensive ... as well as a frickin' huge file!) A quick check on the image you posted gives roughly 24" x 77" which at 300dpi is 7200 x 23100 or around 166 MB.

The next common size up is 44", and then 60", with the other dimension again being dictated by the maximum length of the paper roll. (And your budget. And your computer's processing power.)

Mark

P.S. the 24" dimension and 2:3 aspect ratio are why 24" x 36" is a common poster size.

If you're not too far from a ratio that's offered by your print site of choice, you can just add a white border yourself in Photoshop. Then you can either trim the photo after you receive it, or frame it with the white border (which may even emphasize your longer-than-average print).